HL was pretty fab back in the day, but I don't have any interest in it now. Duke Nukem 3D was much more influential in turning me into an FPS fan.
HL2 was alright but didn't feel like much of a leap and bothered me in several ways. The silent hero thing is all fine and dandy in stuff like Doom where you're just a grunt following orders, and it worked in HL, but in HL2 it was all "Oh wow, Gordon Freeman? THE Gordon Freeman? This is so exciting, you're such a great hero to us all. Now run along and do exactly as I say errand boy."
And why the hell does Alyx seem to have a romantic interest in a man without a personality, too rude to say a single word to her? Maybe they were going for "YOU are Gordon Freeman, so Alyx loves YOU" or something, but to me it just makes her pathetic. She belongs in a Sci-Fi Channel Original.